1. Field of the Invention
This invention relates to a disk cramp apparatus which rotates a spindle hub by holding a disk (media) between the spindle hub and a collet to access the disk.
2. Related Background Art
As shown in FIG. 4, in a conventional disk cramp apparatus of this type, a disk 2 is inserted between a collet 1 and a spindle hub 3 and collet 1 is then fitted into spindle hub 3 to hold the disk therebetween.
However, disk 2 is not always positioned concentric with the spindle hub. For example, as shown by 2b in FIG. 5, disk 2 may be bent and held between collet 1 and spindle hub 3. The accuracy of a central opening in disk 2, damaged due to such miscramping, is very low to greatly reduce the reliability of data storage.
In order to prevent such miscramping, a device has been proposed which performs a cramp operation while rotating the spindle hub when power to the device has been turned on in advance. In this case, turn on of power in advance is a precondition, so that if cramping is performed when power has not been turned on due to the operator's carelessness and/or lack of understanding, miscramping similar to the above would occur.